Closure phase in high-resolution optical imaging

  title={Closure phase in high-resolution optical imaging},
  author={J. E. Baldwin and Christopher A. Haniff and Craig Mackay and Peter J. Warner},
The angular resolution of long-exposure optical images taken with large telescopes at the best sites is limited by atmospheric phase fluctuations to ∼0.5–1 arc s; that is, ∼10–50 times worse than the theoretical diffraction limit. In contrast, the measurement of visibilities and closure phases of fringe patterns in short-exposure images, taken through an aperture mask comprising a non-redundant array of three or more holes, offers the prospect of reliable diffraction-limited imaging using… 
Phase Closure Imaging - Theory & Practice
The current status of the phase closure method in high-resolution optical imaging is reviewed. The various schemes for its application and use at large telescopes are discussed, with particular
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Interferometric Imaging in Optical Astronomy
The atmosphere of the earth restricts the resolution of conventional astronomical imaging to about 1″. Much higher resolution can be obtained by speckle methods. Speckle interferometry, the
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The goal of future optical aperture synthesis telescopes is to achieve model independent imaging of complex sky structure with the success demonstrated in very long baseline radio interferometry.
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Through selection of short exposure images we achieve diffraction-limited I-band imaging from well-figured ground-based telescopes as large as 2.5 m diameter. The faint limiting magnitude and large
Origins of sparse aperture imaging
  • T. Pauls
  • Physics
    2001 IEEE Aerospace Conference Proceedings (Cat. No.01TH8542)
  • 2001
Sparse aperture imaging has its roots in the work on optical interferometry by Fizeau and Michelson over one-hundred years ago, and the development of radio astronomy nearly fifty years later. In
Diffraction-limited imaging with partially redundant masks. I. Infrared imaging of bright objects
The decrease in redundancy resulting from apodizing the telescope pupil results in an enhancement of the quality of reconstructed images at high light levels, which is particularly valuable when short-term variations in the statistics of the atmosphere make the seeing calibration of speckle interferograms difficult.
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In this paper a technique is outlined that can be used in an optical interferometer, and that in many applications offers the possibility of eliminating the problem of atmospheric seeing when
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L'image CCD de haute resolution de Cygnus A, avec FWHM=0,65'' revele une structure considerable dans les 2 kpc du centre. Cygnus A se trouve le mieux decrit par une collision de galaxies